Cancer-related fatigue can be caused by the cancer itself as well as cancer treatments such as chemotherapy, surgery, radiation therapy, bone marrow transplants or hormone therapy.1
Changes in hormone levels and proteins that regulate inflammatory processes can lead to increased levels of fatigue.4
Some cancer treatments and cancers that have spread to the bone marrow can reduce the amount of red blood cells in your body which can cause anaemia (or low iron), making you feel more tired.4
Other cancer treatments may have side-effects, such as nausea or vomiting, which can reduce your appetite and impact on your sleep, contributing to your fatigue.
Certain tumours secret toxins which can prevent healthy cells from producing necessary nutrients such as calcium and potassium for optimal muscle function, resulting in weakness and tiredness.3